Many automobile and boat owners are plagued with the problem of the unauthorized intrusion of their vehicles. Owners whose vehicles have soft coverings such as canvas have increased problems since intrusion is easy. Boat owners especially have large amounts of expensive equipment that is presently secured only by a canvas cover that readily snaps and unsnaps.
The Topputo U.S. Pat. No. 4,253,084 solves the aforementioned problem by providing an alarm system which is actuated by the unfastening of the snap fastener used on protective coverings such as in automobiles and boats. However, in many cases it is desirable to use only a few of the snap switch alarm type-snaps of the Topputo U.S. Pat. No. '084, and to use conventional snap fasteners for the remainder, in order to reduce the overall expense. Two problems occur when this is done. First, a clever thief can lift up the edge of the canvas cover to see the base of the male snap element, and can thus tell the difference between a conventional snap fastener, which can then be attacked without fear of giving an alarm, and the snap sWitch alarm of the Topputo U.S. Pat. No. '084, which has a radically different base.
In practice, the Topputo device is believed to have been sold more than one year ago in an integrally molded form with the stud projecting upwardly from one surface of the mounting plate and the button switch casing projecting downwardly from the opposite bottom face of the mounting plate. This construction requires that a hole be drilled in the surface on which the device is mounted, such hole being capable of receiving the push button switch and its housing. This further increases the cost.
A second problem lies in the very nature of the conventional snap fastener. Often, these are insufficiently mounted and the male element may pull out of its mounting, especially if it has been subjected to weathering such as occurs in a marine environment. Thus, the conventional male element is mounted with only one screw directly to its center, and this male element will pull right out of whatever it is screwed into; the marine environment causes its metal structure to break down, often causing swelling with oxidation, and this further facilitates its tendency to pull out.